U.S. patent number 10,543,740 [Application Number 15/666,157] was granted by the patent office on 2020-01-28 for lockup clutch for powersplit hybrid transmission.
This patent grant is currently assigned to FORD GLOBAL TECHNOLOGIES, LLC. The grantee listed for this patent is Ford Global Technologies, LLC. Invention is credited to Gregory Daniel Goleski, Matthew David Hammond, David Allen Janson, David Gon Oh.
United States Patent |
10,543,740 |
Oh , et al. |
January 28, 2020 |
Lockup clutch for powersplit hybrid transmission
Abstract
A powertrain includes an engine and an electric machine. The
powertrain further includes a planetary gearset including a a first
rotatable element fixedly coupled to an engine crankshaft, a second
rotatable element fixedly coupled to the electric machine, and a
third rotatable element driveably connected to an intermediate
shaft. The powertrain further includes a lockup clutch configured
to selectively couple two of the first rotatable element, the
second rotatable element, and the third rotatable element.
Inventors: |
Oh; David Gon (Ann Arbor,
MI), Janson; David Allen (Plymouth, MI), Goleski; Gregory
Daniel (Rochester Hills, MI), Hammond; Matthew David
(Dearborn, MI) |
Applicant: |
Name |
City |
State |
Country |
Type |
Ford Global Technologies, LLC |
Dearborn |
MI |
US |
|
|
Assignee: |
FORD GLOBAL TECHNOLOGIES, LLC
(Dearborn, MI)
|
Family
ID: |
65020284 |
Appl.
No.: |
15/666,157 |
Filed: |
August 1, 2017 |
Prior Publication Data
|
|
|
|
Document
Identifier |
Publication Date |
|
US 20190039449 A1 |
Feb 7, 2019 |
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B60K
6/547 (20130101); F16H 3/66 (20130101); B60K
6/365 (20130101); B60K 6/387 (20130101); B60K
6/445 (20130101); Y10S 903/911 (20130101); B60K
2006/4816 (20130101); Y10S 903/914 (20130101); F16H
2200/2007 (20130101); B60Y 2400/73 (20130101); Y10S
903/919 (20130101); B60Y 2200/92 (20130101); F16H
2003/445 (20130101); F16H 2200/2043 (20130101); F16H
2200/0043 (20130101); B60Y 2400/42 (20130101); B60K
2006/381 (20130101) |
Current International
Class: |
B60K
6/547 (20071001); F16H 3/66 (20060101); B60K
6/365 (20071001); B60K 6/387 (20071001); B60K
6/445 (20071001); B60K 6/48 (20071001); F16H
3/44 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Scott; Jacob S.
Assistant Examiner: Wu; Lori
Attorney, Agent or Firm: Kelley; David B. Brooks Kushman
P.C.
Claims
What is claimed is:
1. A powertrain comprising: an engine; an electric machine; a
planetary gearset including a planetary carrier assembly fixedly
coupled to an engine crankshaft, a sun gear fixedly coupled to the
electric machine, and a ring gear driveably connected to an
intermediate shaft; a lockup clutch configured to selectively
couple two of the planetary carrier assembly, the sun gear, and the
ring gear; a second electric machine driveably connected to the
intermediate shaft; a gearing assembly configured to alternately
selectively establish a plurality of proportional speed
relationships between the intermediate shaft and an output shaft; a
second planetary gearset having a second sun gear, a second
planetary carrier assembly, and a second ring gear fixedly coupled
to the output shaft; a third planetary gearset having a third sun
gear fixedly coupled to the intermediate shaft, a third planetary
carrier assembly fixedly coupled to the output shaft, and a third
ring gear selectively coupled to the second planetary carrier
assembly; a first brake configured to selectively hold the second
sun gear against rotation; and a second brake configured to
selectively hold the second planetary carrier assembly against
rotation.
2. The powertrain of claim 1 wherein the plurality of proportional
speed relationships includes four positive speed relationships and
one negative speed relationship.
3. The powertrain of claim 1 wherein the second sun gear is
selectively coupled to the intermediate shaft.
4. The powertrain of claim 1 wherein the gearing assembly further
comprises: a clutch configured to selectively couple the
intermediate shaft to the second planetary carrier assembly.
5. A powertrain comprising: an engine; an electric machine; a
planetary gearset including a planetary carrier assembly fixedly
coupled to an engine crankshaft, a sun gear fixedly coupled to the
electric machine, and a ring gear driveably connected to an
intermediate shaft; a lockup clutch configured to selectively
couple two of the two of the planetary carrier assembly, the sun
gear, and the ring gear; a second electric machine driveably
connected to the intermediate shaft; and a gearing assembly
configured to alternately selectively establish a plurality of
proportional speed relationships between the intermediate shaft and
an output shaft; a second planetary gearset having a second sun
gear, a second planetary carrier assembly, and a second ring gear
fixedly coupled to the output shaft; a third planetary gearset
having a third sun gear selectively coupled to the intermediate
shaft, a third planetary carrier assembly fixedly coupled to the
output shaft, and a third ring gear fixedly coupled to the second
planetary carrier assembly; a first brake configured to selectively
hold the second sun gear against rotation; and a second brake
configured to selectively hold the second planetary carrier
assembly against rotation.
6. The powertrain of claim 5 wherein the second sun gear is
selectively coupled to the intermediate shaft.
7. The powertrain of claim 5 wherein the gearing assembly further
comprises: a clutch configured to selectively couple the
intermediate shaft to the second planetary carrier assembly.
8. A powertrain comprising: an engine; an electric machine; a
planetary gearset including a planetary carrier assembly fixedly
coupled to an engine crankshaft, a sun gear fixedly coupled to the
electric machine, and a ring gear driveably connected to an
intermediate shaft; a lockup clutch configured to selectively
couple two of the two of the planetary carrier assembly, the sun
gear, and the ring gear; a second electric machine driveably
connected to the intermediate shaft; and a gearing assembly
configured to alternately selectively establish a plurality of
proportional speed relationships between the intermediate shaft and
an output shaft; a second planetary gearset having a second sun
gear selectively coupled to the intermediate shaft, a second
planetary carrier assembly, and a second ring gear; a third
planetary gearset having a third sun gear fixedly coupled to the
second sun gear, a third planetary carrier assembly fixedly coupled
to the output shaft, and a third ring gear fixedly coupled to the
second planetary carrier assembly; a first brake configured to
selectively hold the second ring gear against rotation; and a
second brake configured to selectively hold the third ring gear
against rotation.
9. The powertrain of claim 8 wherein the second ring gear is
selectively coupled to the intermediate shaft.
10. The powertrain of claim 8 wherein the gearing assembly further
comprises: a clutch configured to selectively couple the
intermediate shaft to the second planetary carrier assembly.
11. A powertrain comprising: an engine; an electric machine; a
planetary gearset including a planetary carrier assembly fixedly
coupled to an engine crankshaft, a sun gear fixedly coupled to the
electric machine, and a ring gear driveably connected to an
intermediate shaft; a lockup clutch configured to selectively
couple two of the two of the planetary carrier assembly, the sun
gear, and the ring gear; a second electric machine driveably
connected to the intermediate shaft; and a gearing assembly
configured to alternately selectively establish a plurality of
proportional speed relationships between the intermediate shaft and
an output shaft; a second planetary gearset having a second sun
gear selectively coupled to the intermediate shaft, a second
planetary carrier assembly selectively coupled to the intermediate
shaft, and a second ring gear fixedly coupled to the output shaft;
a third planetary gearset having a third sun gear, a third
planetary carrier assembly fixedly coupled to the output shaft, and
a third ring gear fixedly coupled to the second planetary carrier
assembly; and a first brake configured to selectively hold the
third sun gear against rotation.
12. The powertrain of claim 11 wherein the gearing assembly further
comprises: a second brake configured to selectively hold the second
planetary carrier assembly against rotation.
13. The powertrain of claim 11 wherein the gearing assembly further
comprises: a third brake configured to selectively hold the second
sun gear against rotation.
14. A powertrain comprising: an engine; an electric machine; a
planetary gearset including a planetary carrier assembly fixedly
coupled to an engine crankshaft, a sun gear fixedly coupled to the
electric machine, and a ring gear driveably connected to an
intermediate shaft; a lockup clutch configured to selectively
couple two of the planetary carrier assembly, the sun gear, and the
ring gear; a second electric machine driveably connected to the
intermediate shaft; and a gearing assembly configured to
alternately selectively establish a plurality of proportional speed
relationships between the intermediate shaft and an output shaft; a
second planetary gearset having a second sun gear selectively
coupled to the intermediate shaft, a second planetary carrier
assembly selectively coupled to the intermediate shaft, and a
second ring gear fixedly coupled to the output shaft; a third
planetary gearset having a third sun gear fixedly coupled to the
second sun gear, a third planetary carrier assembly fixedly coupled
to the output shaft, and a third ring gear; and a first brake
configured to selectively hold the third ring gear against
rotation.
15. The powertrain of claim 14 wherein the gearing assembly further
comprises: a second brake configured to selectively hold the second
planetary carrier assembly against rotation.
16. The powertrain of claim 14 wherein the gearing assembly further
comprises: a third brake configured to selectively hold the second
sun gear against rotation.
Description
TECHNICAL FIELD
This disclosure relates to the field of automatic transmissions for
motor vehicles. More particularly, the disclosure pertains to an
arrangement of gears, clutches, motors, and the interconnections
among them in a power transmission.
BACKGROUND
Many vehicles are used over a wide range of vehicle speeds,
including both forward and reverse movement. Some types of engines,
however, are capable of operating efficiently only within a narrow
range of speeds. Consequently, transmissions capable of efficiently
transmitting power at a variety of speed ratios are frequently
employed. When the vehicle is at low speed, the transmission is
usually operated at a high speed ratio such that it multiplies the
engine torque for improved acceleration. At high vehicle speed,
operating the transmission at a low speed ratio permits an engine
speed associated with quiet, fuel efficient cruising. Typically, a
transmission has a housing mounted to the vehicle structure, an
input driven by an engine crankshaft, often via a launch device
such as a torque converter, and an output driving the vehicle
wheels, often via a differential assembly which permits the left
and right wheel to rotate at slightly different speeds as the
vehicle turns. In front wheel drive vehicles with transverse
mounted engines, the engine crankshaft axis is typically offset
from the axle axis.
Hybrid electric transmissions further reduce fuel consumption by
including one or more reversible electric machines and some type of
electrical energy storage such as a battery. Hybrid electric
transmissions improve fuel efficiency is several ways. Most
internal combustion engines are most efficient when operated at
relatively high power settings. A hybrid electric transmission
permits operating the engine part of the time at a higher power
level than needed for propulsion while storing the excess power in
the battery. Then, at other times, the engine is shut off and the
vehicle is propelled using the stored energy. Although the engine
generates the same amount of total energy, it operates at a higher
average efficiency. Also, when the brakes are applied, the
reversible electrical machine may capture the vehicle kinetic
energy and store it in the battery for later use for propulsion.
When the vehicle is stationary and therefore does not require
propulsion, the engine can be shut off to eliminate the fuel that
would otherwise be used to maintain an idle speed. The electric
motor provides the ability to propel the vehicle with the engine
off and to rapidly restart the engine when necessary.
SUMMARY
In at least one approach, a powertrain is provided. The powertrain
may include an engine and an electric machine. The powertrain may
further include a planetary gearset including a first rotatable
element fixedly coupled to an engine crankshaft, a second rotatable
element fixedly coupled to the electric machine, and a third
rotatable element driveably connected to an intermediate shaft. The
powertrain may further include a lockup clutch configured to
selectively couple two of the first rotatable element, the second
rotatable element, and the third rotatable element.
The first rotatable element may be a planetary carrier assembly.
The second rotatable element may be a sun gear. The third rotatable
element may be a ring gear. In one example, the lockup clutch is
configured to selectively couple the planetary carrier assembly to
the ring gear. In another example, the lockup clutch is configured
to selectively couple the sun gear to the ring gear. In still
another example, the lockup clutch is configured to selectively
couple the sun gear to the planetary carrier assembly.
The powertrain may further include a second electric machine
driveably connected to the intermediate shaft. The powertrain may
also include a gearing assembly configured to alternately
selectively establish a plurality of proportional speed
relationships between the intermediate shaft and an output shaft.
The plurality of proportional speed relationships may include four
positive speed relationships and one negative speed
relationship.
In at least one approach, the gearing assembly includes a second
planetary gearset having a second sun gear selectively coupled to
the intermediate shaft, a second planetary carrier assembly, and a
second ring gear fixedly coupled to the output shaft. In this
approach, the gearing assembly may further include a third
planetary gearset having a third sun gear fixedly coupled to the
intermediate shaft, a third planetary carrier assembly fixedly
coupled to the output shaft, and a third ring gear selectively
coupled to the second planetary carrier assembly. The gearing
assembly may further include a first brake configured to
selectively hold the second sun gear against rotation, and a second
brake configured to selectively hold the second planetary carrier
assembly against rotation. The gearing assembly may further include
a clutch configured to selectively couple the intermediate shaft to
the second planetary carrier assembly.
In at least one approach, the gearing assembly includes a second
planetary gearset having a second sun gear selectively coupled to
the intermediate shaft, a second planetary carrier assembly
selectively coupled to the intermediate shaft, and a second ring
gear fixedly coupled to the output shaft. In this approach, the
gearing assembly may further include a third planetary gearset
having a third sun gear selectively coupled to the intermediate
shaft, a third planetary carrier assembly fixedly coupled to the
output shaft, and a third ring gear fixedly coupled to the second
planetary carrier assembly. The gearing assembly may further
include a first brake configured to selectively hold the second sun
gear against rotation and a second brake configured to selectively
hold the second planetary carrier assembly against rotation. The
gearing assembly may further include a clutch configured to
selectively couple the intermediate shaft to the second planetary
carrier assembly.
In at least one approach, the gearing assembly includes a second
planetary gearset having a second sun gear selectively coupled to
the intermediate shaft, a second planetary carrier assembly, and a
second ring gear selectively coupled to the intermediate shaft. In
this approach, the gearing assembly may further include a third
planetary gearset having a third sun gear fixedly coupled to the
second sun gear, a third planetary carrier assembly fixedly coupled
to the output shaft, and a third ring gear fixedly coupled to the
second planetary carrier assembly. The gearing assembly may further
include a first brake configured to selectively hold the second
ring gear against rotation, and a second brake configured to
selectively hold the third ring gear against rotation. The gearing
assembly may further include a clutch configured to selectively
couple the intermediate shaft to the second planetary carrier
assembly.
In at least one approach, the gearing assembly includes a second
planetary gearset having a second sun gear selectively coupled to
the intermediate shaft, a second planetary carrier assembly
selectively coupled to the intermediate shaft, and a second ring
gear fixedly coupled to the output shaft. In this approach, the
gearing assembly may further include a third planetary gearset
having a third sun gear, a third planetary carrier assembly fixedly
coupled to the output shaft, and a third ring gear fixedly coupled
to the second planetary carrier assembly. The gearing assembly may
further include a first brake configured to selectively hold the
second planetary carrier assembly against rotation, and a second
brake configured to selectively hold the third sun gear against
rotation. The gearing assembly may further include a third brake
configured to selectively hold the second sun gear against
rotation.
In at least one approach, the gearing assembly includes aa second
planetary gearset having a second sun gear selectively coupled to
the intermediate shaft, a second planetary carrier assembly
selectively coupled to the intermediate shaft, and a second ring
gear fixedly coupled to the output shaft. In this approach, the
gearing assembly may further include a third planetary gearset
having a third sun gear fixedly coupled to the second sun gear, a
third planetary carrier assembly fixedly coupled to the output
shaft, and a third ring gear. The gearing assembly may further
include a first brake configured to selectively hold the second
planetary carrier assembly against rotation, and a second brake
configured to selectively hold the third ring gear against
rotation. The gearing assembly may further include a third brake
configured to selectively hold the second sun gear against
rotation.
In at least one approach, the third rotatable element is a
rotatable output element driveably connected to an intermediate
shaft. The lockup clutch may be adapted to selectively couple two
of the first rotatable element, the second rotatable element, and
the third rotatable element to sync a speed of the intermediate to
a speed of the engine crankshaft.
In at least one approach, a planetary gearset is provided. The
planetary gearset may include a planetary carrier assembly fixedly
coupled to an engine crankshaft, a sun gear fixedly coupled to the
electric machine, and a ring gear driveably connected to an
intermediate shaft. The powertrain may further include a lockup
clutch configured to selectively couple the sun gear to the
planetary carrier assembly, the sun gear to the ring gear, or the
ring gear to the planetary carrier assembly.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic representation of a powersplit powertrain
system.
FIG. 2 is a schematic representation of a powersplit powertrain
system including a lockup clutch.
FIG. 3 is a schematic representation of a first transmission
gearing arrangement.
FIG. 4 is a schematic representation of a second transmission
gearing arrangement.
FIG. 5 is a schematic representation of a third transmission
gearing arrangement.
FIG. 6 is a schematic representation of a fourth transmission
gearing arrangement.
FIG. 7 is a schematic representation of a fifth transmission
gearing arrangement.
DETAILED DESCRIPTION
Embodiments of the present disclosure are described herein. It is
to be understood, however, that the disclosed embodiments are
merely examples and other embodiments may take various and
alternative forms. The figures are not necessarily to scale; some
features could be exaggerated or minimized to show details of
particular components. Therefore, specific structural and
functional details disclosed herein are not to be interpreted as
limiting, but merely as a representative basis for teaching one
skilled in the art to variously employ the present invention. As
those of ordinary skill in the art will understand, various
features illustrated and described with reference to any one of the
figures may be combined with features illustrated in one or more
other figures to produce embodiments that are not explicitly
illustrated or described. The combinations of features illustrated
provide representative embodiments for typical applications.
Various combinations and modifications of the features consistent
with the teachings of this disclosure, however, could be desired
for particular applications or implementations.
A group of rotating elements are fixedly coupled to one another if
they are constrained to rotate at the same speed about the same
axis in all operating conditions. Rotating elements can be fixedly
coupled by spline connections, welding, press fitting, machining
from a common solid, or other means. Slight variations in
rotational displacement between fixedly coupled elements can occur
such as displacement due to lash or shaft compliance. One or more
rotating elements that are all fixedly coupled to one another may
be called a shaft. In contrast, two rotating elements are
selectively coupled by a shift element when the shift element
constrains them to rotate at the same speed about the same axis
whenever it is fully engaged and they have different rotational
speeds about that axis in at least some other operating condition.
Two rotatable elements are driveably connected or coupled if there
is a fixed proportional speed relationship between them
A shift element that holds a rotating element against rotation by
selectively coupling it to a fixed housing is called a brake. A
shift element that selectively couples two or more rotatable
elements to one another is called a clutch. Shift elements may be
actively controlled devices such as hydraulically or electrically
actuated clutches or brakes or may be passive devices such as one
way clutches or brakes. Shift elements may be positive engagement
devices such as dog clutches or friction devices capable of
transmitting torque between elements in the presence of relative
rotation. Two elements are coupled if they are either fixedly
coupled or selectively coupled.
A gearing arrangement is a collection of gearing elements and shift
elements configured to impose specified speed relationships among a
set of shafts. A speed relationship is fixedly imposed by a gearing
arrangement if it is imposed regardless of the state of any shift
elements. A speed relationship is selectively imposed by a gearing
arrangement if the speed relationship is imposed only when
particular shift elements of the gearing arrangement are fully
engaged. The speed of a shaft is positive when the shaft rotates in
one direction and negative when the shaft rotates in the opposite
direction. A proportional speed relationship exists between a first
shaft and a second shaft when the ratio of their speeds is
constrained to be a predetermined value. A proportional speed
relationship between a first shaft and a second shaft is an
underdrive relationship if the ratio of the second shaft speed to
the first shaft speed is between zero and one. Similarly, a
proportional speed relationship between a first shaft and a second
shaft is an overdrive relationship if the ratio of the second shaft
speed to the first shaft speed is greater than one. A linear speed
relationship exists among an ordered list of shafts when i) the
first and last shaft in the ordered list are constrained to have
the most extreme speeds, ii) the speeds of the remaining shafts are
each constrained to be a weighted average of the speeds of the
first and last shafts with predetermined weightings, and iii) when
the speeds of the shafts differ, they are constrained to be in the
listed order, either increasing or decreasing.
Referring to FIG. 1, a hybrid electric vehicle (HEV) includes a
powersplit powertrain 10. The vehicle may include a vehicle system
controller (VSC) and powertrain control module (PCM) 12 for
controlling an electric traction battery 14. The battery 14 may
have a two-way electrical connection, whereby it receives and
stores electric energy and also supplies the energy to an electric
traction motor 16. The controller 12 may also control the operation
of an internal combustion engine (ICE) 18. Both the motor 16 and
the engine 18 are capable of powering a transmission 20 that
ultimately delivers torque to the wheels of the vehicle.
The engine 18 delivers power to a torque input shaft, such as
crankshaft 22, that is connected to a planetary gear set 24, for
example, through a one way clutch. The crankshaft 22 powers the
planetary gear set 24 that includes a ring gear 26, a sun gear 28,
and a planetary carrier assembly 30. The crankshaft 22 is driveably
connected to the carrier assembly 30 to power the planetary gear
set 24. The planetary gear set 24 may distribute torque to an
intermediary shaft 34.
The sun gear 28 is driveably connected to a generator 32. The
generator 32 may be engaged with the sun gear 28, such that the
generator 32 may either rotate with the sun gear 28, or not rotate
with it. When the one way clutch couples the engine 18 to the
planetary gear set 24, the generator 32 generates energy as a
reactionary element to the operation of the planetary gear set 24.
Electric energy generated from the generator 32 may be transferred
to the battery 14 through electrical connections 36. The battery 14
also receives and stores electric energy through regenerative
braking, in known fashion. The battery 14 supplies the stored
electric energy to the motor 16 for operation. The portion of the
power delivered from the engine 18 to the generator 32 may also be
transmitted directly to the motor 16. The battery 14, motor 16, and
generator 32 are each interconnected in a two-way electric flow
path through electrical connections 36.
The vehicle may be powered by the engine 18 alone, by the battery
14 and motor 16 alone, or by a combination of the engine 18 with
the battery 14 and motor 16. In a first mode of operation, the
engine 18 is activated to deliver torque through the planetary gear
set 24. The ring gear 26 may distribute torque through the
intermediary shaft 34 to step ratio gears 38, which may, for
example, comprise meshing gear elements 40, 42, 44, and 46. Gears
42, 44, and 46 are mounted on a countershaft, and gear 46
distributes torque to gear 48. Gear 48 then distributes torque to a
torque output shaft or countershaft 50. In the first mode of
operation, the motor 16 may also be activated to assist in the
engine 18. When the motor 16 is active in assisting, gear 52
distributes torque to gear 44 and to the countershaft.
In a second mode of operation, or EV mode, the engine 18 is
disabled or otherwise prevented from distributing torque to the
torque output shaft 50. In the second mode of operation, the
battery 14 powers the motor 16 to distribute torque through the
step ratio gears 38 and to the torque output shaft 50.
The torque output shaft 50 is connected to a differential and axle
mechanism 56 which distributes torque to traction wheels 58. The
controller 12 controls the battery 14, engine 18, motor 16 and
generator 32 in order to distribute torque to the wheels 58 in
either the first mode of operation or the second mode of
operation.
As previously described, there are two power sources for the
driveline. The first power source is the engine 18, which delivers
torque to the planetary gear set 24. The other power source
involves only the electric drive system, which includes the motor
16, the generator 32 and the battery 14, where the battery 14 acts
as an energy storage medium for the generator 32 and the motor 16.
The generator 32 may be driven by the planetary gear set 24, and
may alternatively act as a motor and deliver power to the planetary
gear set 24.
Referring now to FIGS. 2-4, the powertrain 10 may further include a
lockup clutch 60. The lockup clutch 60 may be adapted to lock up
the planetary gear set 24 of the transmission 20. In at least one
approach, shown in FIG. 2, the lockup clutch 60 is adapted to lock
the ring gear 26 and the planetary carrier assembly 30. In at least
one other approach, shown in FIG. 3, the lockup clutch 60 is
adapted to lock the sun gear 28 and the planetary carrier assembly
30. In at least one other approach, shown in FIG. 4, the lockup
clutch 60 is adapted to lock the ring gear 26 and the sun gear
28.
Lockup of the planetary gear set 24 by the lockup clutch 60 causes
the gears of the ring gear 26, sun gear 28, and planetary carrier
30 to mesh and "lock up," thus transmitting torque from the engine
18 to the transmission 20. In this way, the elements of the
planetary gear set 24 rotate in unison with a 1 to 1 speed ratio.
Lockup of the planetary gear set 24 by the lockup clutch 60 may
reduce or eliminate mesh loss in the planetary gear set 24, thereby
improving transmission efficiency when in the locked-up
configuration.
The transmission 20 may include a gearing-arrangement that may be
disposed, for example, at location L1, location L2, or location
L3.
Referring now to FIG. 3, a first gearing-arrangement 70 may include
a first planetary gear set 72 that includes a ring gear 74, a sun
gear 76, and a planetary carrier assembly 78. The first
gearing-arrangement 70 may include a second planetary gear set 80
that includes a ring gear 82, a sun gear 84, and a planetary
carrier assembly 86.
In at least one approach, the sun gear 76 is selectively coupled to
an input 62 by clutch 94. In at least another approach, the first
gearing-arrangement 70 does not include clutch 94. In this way, the
first gearing-arrangement 70 may provide four forward speeds
without a reverse clutch.
Brake 96 selectively couples sun gear 76 to a housing to
selectively hold it against rotation. The planetary carrier
assembly 78 is selectively coupled to the input 62 by clutch 92.
The planetary carrier assembly 78 is also selectively coupled to
ring gear 82 by clutch 90. Ring gear 74 is fixedly coupled to
planetary carrier assembly 86. The planetary carrier assembly 86 is
fixedly coupled to output 50. Sun gear 84 is fixedly coupled to the
input 62.
In at least one approach, the first gearing-arrangement 70 does not
include clutch 94 or brake 98. In this way, the first
gearing-arrangement 70 may provide three forward speeds without a
reverse clutch.
Various power flow paths between input shaft 62 and output shaft 50
are established by the selective engagement of the clutches and
brakes of the first gearing-arrangement 70. As shown in Table 1,
engaging the shift elements in combinations of two or three
establishes four forward speed ratios and one reverse speed ratio
between input 62 and output 50. An X indicates that the shift
element is required to establish the power transfer path. An (X)
indicates that the shift element may be engaged in that speed ratio
but is not required to establish the power transfer path.
TABLE-US-00001 TABLE 1 90 92 94 96 98 Ratio Step 1st X X 3.00 2nd X
X 1.67 1.80 3rd X X (X) 1.00 1.67 4th X X 0.67 1.50 Rev X X -2.00
67%
Referring now to FIG. 4, a second gearing-arrangement 100 may
include a first planetary gear set 102 that includes a ring gear
104, a sun gear 106, and a planetary carrier assembly 108. The
second gearing-arrangement 100 may include a second planetary gear
set 110 that includes a ring gear 112, a sun gear 114, and a
planetary carrier assembly 116.
In at least one approach, the sun gear 106 is selectively coupled
to an input 62 by clutch 124. In at least another approach, the
second gearing-arrangement 100 does not include clutch 124. In this
way, the second gearing-arrangement 100 may provide four forward
speeds without a reverse clutch.
Brake 126 selectively couples sun gear 106 to a housing to
selectively hold it against rotation. The planetary carrier
assembly 108 is selectively coupled to the input 62 by clutch 122.
The planetary carrier assembly 108 is fixedly coupled to ring gear
112. Brake 128 selectively couples the planetary carrier assembly
108 and ring gear 112 to the housing to selectively hold them
against rotation. Ring gear 104 is fixedly coupled to planetary
carrier assembly 116. The planetary carrier assembly 116 is fixedly
coupled to output 50. Sun gear 114 is selectively coupled to the
input 62 by clutch 120.
In at least one approach, the second gearing-arrangement 100 does
not include clutch 124 or brake 128. In this way, the second
gearing-arrangement 100 may provide three forward speeds without a
reverse clutch.
Various power flow paths between input shaft 62 and output shaft 50
are established by the selective engagement of the clutches and
brakes of the second gearing-arrangement 100. As shown in Table 2,
engaging the shift elements in combinations of two or three
establishes four forward speed ratios and one reverse speed ratio
between input 62 and output 50. An X indicates that the shift
element is required to establish the power transfer path. An (X)
indicates that the shift element may be engaged in that speed ratio
but is not required to establish the power transfer path.
TABLE-US-00002 TABLE 2 120 122 124 126 128 Ratio Step 1st X X 3.00
2nd X X 1.67 1.80 3rd X X (X) 1.00 1.67 4th X X 0.67 1.50 Rev X X
-2.00 67%
Referring now to FIG. 5, a third gearing-arrangement 130 may
include a first planetary gear set 132 that includes a ring gear
134, a sun gear 136, and a planetary carrier assembly 138. The
third gearing-arrangement 130 may include a second planetary gear
set 140 that includes a ring gear 142, a sun gear 144, and a
planetary carrier assembly 146.
Sun gear 136 is selectively coupled to an input 62 by clutch 150.
Sun gear 136 is fixedly coupled to sun gear 144. The planetary
carrier assembly 138 is selectively coupled to the input 62 by
clutch 152. The planetary carrier assembly 138 is fixedly coupled
to ring gear 142. Brake 158 selectively couples the planetary
carrier assembly 138 and ring gear 112 to a housing to selectively
hold them against rotation.
In at least one approach, the ring gear 134 is selectively coupled
to the input 62 by clutch 154. In at least another approach, the
third gearing-arrangement 130 does not include clutch 154. In this
way, the third gearing-arrangement 130 may provide four forward
speeds without a reverse clutch.
Brake 156 selectively couples ring gear 136 to the housing to
selectively hold it against rotation. The planetary carrier
assembly 146 is fixedly coupled to output 50.
In at least one approach, the third gearing-arrangement 130 does
not include clutch 154 or brake 158. In this way, the third
gearing-arrangement 130 may provide three forward speeds without a
reverse clutch.
Various power flow paths between input shaft 62 and output shaft 50
are established by the selective engagement of the clutches and
brakes of the third gearing-arrangement 130. As shown in Table 3,
engaging the shift elements in combinations of two or three
establishes four forward speed ratios and one reverse speed ratio
between input 62 and output 50. An X indicates that the shift
element is required to establish the power transfer path. An (X)
indicates that the shift element may be engaged in that speed ratio
but is not required to establish the power transfer path.
TABLE-US-00003 TABLE 3 150 152 154 156 158 Ratio Step 1st X X 3.00
2nd X X 1.67 1.80 3rd X X (X) 1.00 1.67 4th X X 0.67 1.50 Rev X X
-2.00 67%
Referring now to FIG. 6, a fourth gearing-arrangement 160 may
include a first planetary gear set 162 that includes a ring gear
164, a sun gear 166, and a planetary carrier assembly 168. The
fourth gearing-arrangement 160 may include a second planetary gear
set 170 that includes a ring gear 172, a sun gear 174, and a
planetary carrier assembly 176.
Sun gear 166 is selectively coupled to an input 62 by clutch 182.
Brake 184 selectively couples sun gear 166 to a housing to
selectively hold it against rotation. The planetary carrier
assembly 168 is selectively coupled to the input 62 by clutch 180.
The planetary carrier assembly 168 is fixedly coupled to ring gear
172.
In at least one approach, a brake 186 selectively couples the
planetary carrier assembly 168 and ring gear 172 to the housing to
selectively hold them against rotation. In at least another
approach, the fourth gearing-arrangement 160 does not include brake
186. In this way, the fourth gearing-arrangement 160 may provide
four forward speeds without a reverse clutch.
Ring gear 164 is fixedly coupled to the planetary carrier assembly
176. Ring gear 164 and the planetary carrier assembly 176 are
fixedly coupled to the output 50. Brake 186 selectively couples sun
gear 174 to the housing to selectively hold it against
rotation.
In at least one approach, the fourth gearing-arrangement 160 does
not include brake 184 or brake 186. In this way, the fourth
gearing-arrangement 160 may provide three forward speeds without a
reverse clutch.
Various power flow paths between input shaft 62 and output shaft 50
are established by the selective engagement of the clutches and
brakes of the third gearing-arrangement 130. As shown in Table 4,
engaging the shift elements in combinations of two or three
establishes four forward speed ratios and one reverse speed ratio
between input 62 and output 50. An X indicates that the shift
element is required to establish the power transfer path. An (X)
indicates that the shift element may be engaged in that speed ratio
but is not required to establish the power transfer path.
TABLE-US-00004 TABLE 4 180 182 184 186 188 Ratio Step 1st X X 3.00
2nd X X 1.67 1.80 3rd X X 1.00 1.67 4th X X 0.67 1.50 Rev X X -2.00
67%
Referring now to FIG. 7, a fifth gearing-arrangement 190 may
include a first planetary gear set 192 that includes a ring gear
194, a sun gear 196, and a planetary carrier assembly 198. The
fifth gearing-arrangement 190 may include a second planetary gear
set 200 that includes a ring gear 202, a sun gear 204, and a
planetary carrier assembly 206.
Sun gear 196 is selectively coupled to an input 62 by clutch 212.
Sun gear 196 is fixedly coupled to sun gear 204. Brake 214
selectively couples sun gear 196 and sun gear 204 to a housing to
selectively hold them against rotation. The planetary carrier
assembly 198 is selectively coupled to the input 62 by clutch
210.
In at least one approach, a brake 216 selectively couples the
planetary carrier assembly 198 to the housing to selectively hold
it against rotation. In at least another approach, the fifth
gearing-arrangement 190 does not include brake 216. In this way,
the fifth gearing-arrangement 190 may provide four forward speeds
without a reverse clutch.
Ring gear 194 is fixedly coupled to the planetary carrier assembly
206. The planetary carrier assembly 206 is fixedly coupled to
output 50. Brake 218 selectively couples ring gear 202 to the
housing to selectively hold it against rotation.
In at least one approach, the fifth gearing-arrangement 190 does
not include brake 214 or brake 216. In this way, the fifth
gearing-arrangement 190 may provide three forward speeds without a
reverse clutch.
Various power flow paths between input shaft 62 and output shaft 50
are established by the selective engagement of the clutches and
brakes of the third gearing-arrangement 130. As shown in Table 5,
engaging the shift elements in combinations of two or three
establishes four forward speed ratios and one reverse speed ratio
between input 62 and output 50. An X indicates that the shift
element is required to establish the power transfer path. An (X)
indicates that the shift element may be engaged in that speed ratio
but is not required to establish the power transfer path.
TABLE-US-00005 TABLE 5 210 212 214 216 218 Ratio Step 1st X X 3.00
2nd X X 1.67 1.80 3rd X X 1.00 1.67 4th X X 0.67 1.50 Rev X X -2.00
67%
While exemplary embodiments are described above, it is not intended
that these embodiments describe all possible forms encompassed by
the claims. The words used in the specification are words of
description rather than limitation, and it is understood that
various changes may be made without departing from the spirit and
scope of the disclosure. As previously described, the features of
various embodiments may be combined to form further embodiments of
the invention that may not be explicitly described or illustrated.
While various embodiments could have been described as providing
advantages or being preferred over other embodiments or prior art
implementations with respect to one or more desired
characteristics, those of ordinary skill in the art recognize that
one or more features or characteristics may be compromised to
achieve desired overall system attributes, which depend on the
specific application and implementation. These attributes may
include, but are not limited to cost, strength, durability, life
cycle cost, marketability, appearance, packaging, size,
serviceability, weight, manufacturability, ease of assembly, etc.
As such, embodiments described as less desirable than other
embodiments or prior art implementations with respect to one or
more characteristics are not outside the scope of the disclosure
and may be desirable for particular applications.
* * * * *